This is the source Code for Both Wii homebrew Apps Riivolution and RawkSD. The source code was released by one of the developers known as AerialX (Riivolution source code is in the folder marked launcher).
RawkSD is an app that allows you to install custom songs as DLC onto an SD card, and to be played in Rock Band 2.
It also allows importing songs from Rock Band 1 and all Guitar Hero games.
Riivolution is an on-the-fly game patcher for use with retail
discs. It allows users to place content on their SD or USB devices,
which will be read by the game during regular play.
It can be used for custom textures, music, levels, memory patches, game translations, and more!
Both of these apps have been closed source since forever but since the source is available I have decided to post it here that way it is preserved in case it's ever needed.